Blocks connectable by lateral sliding,including means for reducing sliding contact



May 26, 1970 A. FISCHER 3,5 90

BLOCKS CONNECTABLE BY LATERAL SLIDING, INCLUDING MEANS FOR REDUCINGSLIDING CONTACT Filed May 29, 1967 United States Patent O 3,513,590BLOCKS CONNECTABLE BY LATERAL SLIDING, INCLUDING MEANS FOR REDUCINGSLIDING CONTACT Artur Fischer, 133 Gruenmettstetterstrasse, 7241Tumlingen, Kreis Freudenstadt, Germany Filed May 29, 1967, Ser. No.641,820 Claims priority, application Germany, June 4, 1966,

Int. Cl. A63h 33/08 US. C]. 4625 20 Claims ABSTRACT OF THE DISCLOSURE Aconstruction toy kit having blocks with mating undercut heads andgrooves. The blocks are connected by lateral sliding of a head into agroove, and include contactreducing means projecting from the block faceadjacent the head for preventing surface-to-surface contact of the facewith a similar face on an other building block in response to matingengagement of the coupling means with complementary coupling meansprovided on such other building block.

CROSS-REFERENCE TO RELATED APPLICATIONS 'Ser. No. 595,071, filed on Nov.17, 1966 and entitled Construction Kit.

BACKGROUND OF THE INVENTION The present invention relates to building orassembly kits in general, and more particularly to toy building orassembly kits for the erection of replicas of buildings, vehicles andthe like.

Building or assembly kits are known, for instance from myabove-identified copending application and from others, in which aplurality of structural elements in form of building blocks areprovided. These building blocks have male, female, or male and femalecoupling portions so that they can be connected to one another by matingof complementary coupling portions.

As set forth in the above-mentioned copending application, thesecoupling portions are in form of undercut grooves provided in one ormore surfaces of the building blocks, and in form of complementary malecoupling heads which are also undercut and project from one or moresurfaces of the same or other building blocks. To effect connection oftwo blocks, a coupling head of one block is introduced into a groove ofanother, usually from an open end of the groove, and the coupling headis then shifted in the groove until the two blocks are in their desiredrelative positions.

During such shifting, experience has shown, undue friction developsbetween the juxtaposed surfaces of the two blocks, it being understoodthat these surfaces are tightly pressed against one another. Instead ofsmoothly gliding one on the other, the blocks therefore undergo a ratherjerky motion which is undesirable and which is particularly pronouncedif the two blocks are made from synthetic plastic material, as isusuallythe case. An improvement in this is thus clearly desirable.

SUMMARY OF THE INVENTION The present invention provides this desiredimprovement.

More particularly, the present invention very substan tially reduces thefriction between the juxtaposed faces of blocks, which are connected asdiscussed above. It achieves thus reduction in friction by significantlyreducing the area of contact between the juxtaposed surfaces.

Briefly stated, one feature of my invention resides in the provision ofa building block having a face; coupling ice means provide on the face;and friction-reducing means projecting from the face for preventingsurface-to-surfacc contact of the face with a similar face on an otherbuilding block in response to mating engagement of the coupling meanswith complementary coupling means provided on such other building block.

The friction-reducing means is provided in form of projections which mayhave various configurations and whose surface portions which are to bein engagement with a surface of another block, are preferably convexlycurved to further reduce the area of contacts.

The friction-reducing means in accordance with the present invention maybe integral with the building block itself, or it may be provided on orintegral with the coupling means. Also, it may be of the same materialas the building block, or of a different material which may be the sameas the material of the coupling means.

The novel features which are considered as characteristic for theinvention are set forth in particular in the appended claims. Theinvention itself, however, both as to its construction and its method ofoperation, together with additional objects and advantages thereof, willbe best understood from the following description of specificembodiments when read in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a partly sectioned top-planview of one side of a building block incrporating my invention;

FIG. 2 is an end view of the embodiment shown in FIG. 1;

FIG. 3 is a view similar to FIG. 2, but illustrates a somewhat modifiedembodiment;

FIG. 4 shows an end view of an additional embodiment;

FIG. 5 is a longitudinal section through the embodiment shown in FIG. 4;and

FIG. 6 is a fragmentary side elevation, showing two of the buildingblocks illustrated in FIG. 1 coupled together.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Discussing now the drawing indetail, and firstly the embodiment shown in FIGS. 1 and 2 thereof, itwill be noted that these figures illustrate a building block 1 ofpolygonal cross-section and outline. Block 1 is provided in at least oneside face thereof, with an undercut groove 2. It is also provided with asimilar undercut groove 3 in one of its endfaces, and thecross-sectional configuration of groove 3 is identical with that ofgroove 2.

The opposite endface, indicated by the arrow A, is provided with anupwardly extending recess 4 in which there is received a complementarilyconfigurated extension portion 6 of an undercut male coupling head 7,which is integral with the portion 6 and projects outwardly beyond thesame and the endface in which it is secured, in fixed relationshipthereto. The portion 6 is provided with a plurality of radiallyextending wings or ribs 8 (see FIG. 2) which prevent rotation of theportion 6 in the recess 4. The portion is in turn provided with apassage (not numbered) in which one end portion of a pin 5 is received,the other end portion thereof being received in an extension of therecess 4. To secure the pin 5and thereby the portion 6against workingloose, the outer surface of pin 5 is provided with a plurality ofsawtooth shaped ridges which, as illustrated, encircle the pin 5, butwhich might alternately also extend axially thereof.

Each of the wings 8 has, at its end which faces in direction of thecoupling head 7, an abutment or engagement surface portion 9 which, asevident from FIGS. 1 and 2 both, is concavely rounded. The surfaceportions 9 constitute contact-reducing means according to the presentinvention. The depth to which the portion 6 with its wings 8 is insertedinto the recess is so selected that the surface portions 9 project aslight distance beyond the endface in which the recess 4 is provided. Inaccordance with the invention I have found it advantageous that thisdistance be on the order of several hundreds of a millimeter, that is noless than 0.01 mm. and no more than 0.09 mm. (see FIG. 6). Adherence tothis tolerance, in the manufacture of blocks embodying my invention, issimple particularly if, in forcing the portion 6 into the recess 4, thesurface portions 9 on the one hand and the endface in which recess 4 isprovided on the other hand, are engaged by the tool utilized forinserting and forcing the portion 6 into position.

I have also found it advantageous to make the building block 1 itself ofa relatively hard synthetic plastic material, and to make the portions 6and 7 of a more elastic synthetic plastic material. Usual syntheticplastic material for the building block 1 may be polystyrol known underthe trademark Luran and for the portions 6 and 7 acetalcopolymerisatknown under the trademark Hostaform C.

The embodiment in FIG. 3 is substantially similar to that in FIGS. 1 and2 except that, Where in the preceding figures the projecting portions ofthe wings with the surface portions 9 extended radially of the head 7,in FIG. 3 the projecting portion with its abutment-surface portion 20 isof annular outline, surrounding the undercut coupling head 21 which isof quadratic cross-section. To obtain greater elasticity, the surfaceportion 20 may be discontinuous, the interruptions being clearly visiblein FIG. 3.

FIGS. 4 and 5 illustrate still another embodiment of the invention. Asshown in FIG. 4, the coupling head 7a is here of circular cross-section,while the extension portion 6a with the wings 8a corresponds inconfiguration to the portion 6 with the Wings 8 in FIG. 1, as visible inFIG. 5. Unlike the block in FIG. 1, however, the block 1b in FIG. 5 issubstantially quadratic and the distance between two opposite ones ofits faces is so selected as to correspond to the combined embeddedlength of two of the portions 6a. Accordingly, therefore, block 1b isprovided with two recesses corresponding to the recess 4 in FIG. 1, andone of the portions 6a is received in each of these recesses. Further,each end portion of the pin 5a is received in a passage of therespective portion 6a, thus connecting both portions 6a together. Exceptfor these differences the embodiment in FIGS. 4 and 5 corresponds tothat in FIGS. 1 and 2.

FIG. 6, finally, shows two building blocks connected to one another,with block 1 substantially corresponding to that shown in FIG. 1, andblock 1a constituting the auxiliary block with which coupling is to beeffected. Clearly, provision of the projecting surface portions 9 on theprojection-which in this embodiment is of circular outlineresults inspacing between the juxtaposed endfaces of the blocks 1, 1a, althoughthe distance is illustrated in exaggerated form for the sake of clarity,it being recalled that the actual distance is only a few hundreds of amillimeter.

Various possible modifications will be readily apparent. Thus, the pin 5can be secured to the portion 6 via cooperating screw threads and befrictionally secured in the block 1--or vice versa. Further, the angularpositions of the head 7 relative to the block endface can be madeadjustable if the portion 6 is of circular cross-section without thewings 8, and if the pin 5 is threadedly secured to the portion 6.Evidently it is then highly advisable that the screw threads matestiflly enough to prevent undesired rotation of portion 6 and head 7. Ifplastic is used, this is a simple matter, as is well known in the art.

Also, the pin 5 can be eliminated and the portion 6 be made cylindrical.In this case, saw-tooth shaped ridges corresponding to those shown inFIG. 1 on the pin 5, can be provided on the portion 6 itself. It is alsoclear that the head 7 and the projections provided with the surfaceportions 9 can be made integral with the block,

rather than being joined thereto. If this is done on blocks which areused for special applications, the entire block with head andprojections can be made of a materialsuch as a synthetic p1astic-whichis different from that used for making the regular blocks to which thespecial block is to be connected. This facilitates sliding displacementof the blocks relative to one another.

It will be understood that each of the elements decribed above, or twoor more together, may also find a useful application in other types oftoys differing from the types described above.

While the invention has been illustrated and described as embodied inbuilding block, it is not intended to be limited to the details shown,since various modifications and structural changes may be made withoutdeparting in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist ofthe present invention that others can by applying current knowledgereadily adapt it for various applications without omitting featuresthat, from the standpoint of prior art, fairly constitute essentialcharacteristics of the generic or specific aspects of this invention.

What is claimed as new and desired to be protected by Letters Patent isset forth in the appended claims.

1. An assembly kit, comprising a first building block having a firstface and provided thereon with first coupling means; a second buildingblock having a second face; second coupling means provided on saidsecond face, said first coupling means being an undercut groove and saidsecond coupling means being an undercut coupling head in fixedrelationship on said second block and receivable in said groove incoupling relationship only by sliding in a direction longitudinallythereof with freedom of said longitudinal sliding movement; andcontactreducing means located in fixed relationship on said secandbuilding block and projecting from said second face thereof forpreventing surface-to-surface contact of said second face with saidfirst face on said first building block in response to slidingengagement of said first and second coupling means.

2. In an assembly kit as defined in claim 1, wherein said secondcoupling means is integral with said second building block.

3. An assembly kit as defined in claim 1, wherein said contact-reducingmeans comprises a plurality of projections radially spaced from saidsecond coupling means and each having a surface portion spaced from andfacing in the same direction as said second face of said second buildingblock.

4. An assembly kit as defined in claim 1, wherein said contact-reducingmeans projects from said second face by a distance of at least 0.01 mm.and at most 0.09 mm.

5. An assembly kit as defined in claim 1, wherein said contact-reducingmeans comprises at least one projection having a surface portion spacedfrom and facing in the same direction as said second face of said secondbuilding block.

6. An assembly kit as defined in claim. 5, wherein said surface portionin convex.

7. An assembly kit as defined in claim 5, wherein said projection is anannular projection and surrounds said coupling head.

8. An assembly kit as defined in claim 7, wherein said annularprojection is of circular outline.

9. An assembly kit as defined in claim 7, wherein said annularprojection is of polygonal outline.

10. An assembly kit as defined in claim 1, said underout coupling headprojecting from said second face and beyond said contact-reducing meansthereon.

11. An assembly kit as defined in claim 10, wherein said second buildingblock consists of one synthetic plastic material, and at least saidcoupling head consists of another synthetic plastic material.

12. An assembly kit as defined in claim 10, wherein said second face isprovided with a recess extending inwardly therefrom; said secondcoupling means further comprising an extension portion extendingrearwardly from said coupling head and received in said recess.

13. An assembly kit as defined in claim 12, wherein said extensionportion has a cross-sectional area greater than that of said couplinghead and is provided adjacent said head with an exposed surface whichextends laterally beyond said coupling head and is located in thegeneral plane of said second] face, said contact-reducing means beingprovided on said surface.

14. An assembly kit as defined in claim 12, wherein said recess is ofother than circular cross-section, said extension portion having across-section complementary to that of said recess.

15. An assembly kit as defined in claim 12, wherein said recess is of apredetermined depth, said extension portion having a longitudinalextension shorter than said predetermined depth and having an endportion spaced from said coupling head, and said extension portionfurther comprising a pin secured in said end portion and projectingtherefrom in the longitudinal direction of said extension portion.

16. An assembly kit as defined in claim 15, said end portion beingprovided with an internally screw-threaded passage extending inwardlythereof in longitudinal direction of said extension portion; and whereinsaid pin comprises an externally screw-threaded first end portionthreadedly received in said passage, and a second end portionfrictionally retained in said recess of said second face.

17. An assembly kit as defined in claim 15, wherein said pin is madefrom a material other than the material of said extension portion.

18. An assembly kit as defined in claim 17, wherein said material ofsaid pin is a metallic material.

19. An assembly kit as defined in claim 15, said end portion beingprovided with a passage extending inwardly thereof in longitudinaldirection of said extension portion; and wherein said pin isfrictionally retained in said passage and said recess.

20*. An assembly kit as defined in claim 19, wherein said pin has anouter circumferential surface provided with a plurality offriction-promoting ridges.

References Cited UNITED STATES PATENTS 2,649,803 8/ 1953 Andre 46-252,961,779 11/1960 Perry. 2,981,009 4/ 1961 Lindquist 4626 X 3,195,2667/1965 Onanian 46-26 FOREIGN PATENTS 36,679 11/1965 Germany.

F. BARRY SHAY, Primary Examiner

